Jet deflector



Sept. 17, 1968 c, F. PAVLIN ET AL JET DEFLECTOR 5 Sheets-Sheet 1 7 Filed March 20, 1967 WM MQ m Sept. 17, 1968 I FAWN ET AL I 3,401,885

JET DEFLECTOR Filed March 20, 1967 E Sheets-Sheet 2 fare/liar:

Sept. 17, 1968 c. F. PAVLIN ET AL 3,40L885 JET DEFLECTOR V Filed March 20, 1967 s Sheets-Sheet wdzw, a, M m

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United States Patent 3,401,885 JET DEFLECTOR Cyrille Francois Pavlin, Val dAlbian, Yvelines, and Francois Charles Oudin, Noisy-le-Roi, Yvelines, France, assignors to Societe Bertin & Cie, Paris, France, a corporation of France, and Engins Matra Societe Anonyme, Paris, France, a French body corporate Filed Mar. 20, 1967, Ser. No. 624,271 Claims priority, application France, Mar. 22, 1966,

4 Claims. ci. 239-4275 ABSTRACT OF THE DISCLOSURE The deflector according to the invention comprises mainly in combination: a nozzle delivering the propelling jet, and a deflection chamber which follows the nozzle and which terminates at its downstream end as spaced convergent walls between which the jet issues. The nozzle is divergent at least in a portion near the nozzle exit orifice, and that end of the chamber via which the same is connected to the nozzle projects on either side of the nozzle exit orifice, the chamber narrowing in the vicinity of such orifice so that free spaces are left on each side of the jet in the chamber, and control passages are connected to the chamber near the ends thereof to enable the pressure in such spaces to be varied.

This invention relates to a jet deflector which is of use in controlling jet-propelled devices such as aircraft or rockets and which is free from moving parts in contact with the propelling jet and requiring deflection.

The deflector according to the invention comprises mainly in combination: a nozzle delivering the propelling jet, and a deflection chamber which follows the nozzle and which terminates at its downstream end as spaced convergent walls between which the jet issues. The nozzle is divergent at least in a portion near the nozzle exit orifice, and that end of the chamber via which the same is connected to the nozzle projects on either side of the nozzle exit orifice, the chamber narrowing in the vicinity of such orifice so that free spaces are left on each side of the jet in the chamber, and control passages are connected to the chamber near the ends thereof to enable the pressure in such spaces to be varied.

Preferably, the nozzle is adapted to deliver a flattened jet whose normal mean plane coincides with the longitudinal plane of symmetry of the convergent walls; however, the nozzle can deliver a jet of some other shape, for instance, a circular jet.

The jet deflector according to this invention can be used for high Mach number jets and more particularly for supersonic jets. More particularly because the chamber end projects on either side of the nozzle exit orifice, there is less tendency than previously for the jet, which bursts as it leaves the nozzle, the bursting increasing with jet velocity, to stick to the chamber walls, with resulting wall effects which disturb deflector operation. The result is, even in the case of supersonic jets, that correct deviation is maintained and that deviation is progressive and linear relatively to the actuating or control pressures used.

For a better understanding of the invention and to show how the same may be carried into effect, reference may now be made to the accompanying drawings wherein:

FIG. 1 shows an embodiment of the invention in elevation with partial longitudinal sectioning;

FIG. 1a is a plan view corresponding to FIG. 1;

FIG. 2 is a section on the line IIII of FIG. 1;

FIG. 3 is a sectioned view showing details of the control distributor;

FIG. 4 is a plan view, with some parts removed, of a variant comprising a circular cross-section nozzle, and

3,401,885 Patented Sept. 17, 1968 FIG. 5 is a section on the line VV of FIG. 4.

In the embodiment shown in FIGS. 1-3, a jet deflector comprises a divergent nozzle 1 comprising an exit portion 2 which is of flattened shape and which, as can be seen in FIG. 2, is connected to end 3 of a deflection chamber 4. Chamber width near the chamber end 3 is appreciably greater than nozzle width and is preferably substantially twice nozzle width. Chamber length is preferably approximately ten times the width of the nozzle exit orifice; it has been found by experiments that these conditions give the best results.

Chamber side walls 5 substantially extend corresponding walls 6 of nozzle 1, but walls 7, which are shown sectioned in FIG. 1, are further apart from one another than are corresponding walls 8 of nozzle 1 and serve merely to isolate the chamber interior from the environmental space. The walls 7 terminate in plane convergent portions 9a, 9b which are symmetrical of central plane P of the nozzle 1 and of the chamber 4. Edges 10 of the walls 9 are spaced far enough apart for substantially the whole of the jet to pass between the edges 10 when the jet is not deflected.

Near their origin the walls 7 are pierced with transverse control slots 11a, 11b which extend substantially over the whole width of the walls 7 and which passages 12a, 12b connect to a central control box 13, the same communicating via a duct 14 with an auxiliary control fluid source. As FIG. 3 shows, the box 13 comprises a distributor 15, in the form of a symmetrical double valve member 15, 15b which is adapted to be operated externally and which cooperates with symmetrical seats 16a, 16b bounding chambers 17a, 17b to which the passages 12a, 12b extend.

The only difference between the embodiment just described and the embodiment shown in FIGS. 4 and 5 is that in FIGS. 4 and 5 the nozzle 1 is of circular cross-section. End portion 2 is connected to chamber end 3 by means of an outer coupling sleeve or the like 18. Chamber height is substantially constant and equal to nozzle diameter, but, as the chain-dotted lines in FIG. 5 indicate, chamber width near the chamber end 3 is appreciably greater than nozzle diameter.

The operation of the deflector is very simple. Provided that pressures P P operative on either side of the jet are equal, the same goes through the chamber 4 without deflection and its mean plane coincides with the plane P. If, for instance, P is greater than P the jet is deflected to wards the wall 9b, strikes the same and is reflected thereby to issue from the orifice bounded by the edges 10, 10 with a deflection towards the side at the pressure P,,. The reflection produces an aerodynamic lever effect which greatly increases the final deflection as compared with the deflection experienced by the jet in the chamber 4.

The amplitude of the deviation depends upon the difference between the movement quantities of the control jets and/or upon the difference between the static pressures on either side of the jet in the chamber 4. The latter pressure difference can be varied by means of the distributor shown in FIG. 3. The same operates equally well in a dense atmosphere, in a rarified atmosphere and in vacuo; provided that like sides of the valve members experience substantially equal pressures, as is necessary if symmetrical movements of the valve member are to produce symmetrical eifects, the distributor shown in FIG. 3 has a total delivery which is constant for all the positions of the double valve member 15a, 15b.

The arrows refer to operation in a rarified atmosphere or in vacuo. In this case, except in its two end positions the double valve member connects, via two passages bounded by the seats 16a, 16b, both sides of the jet to the environmental rarified space. The last-mentioned two passages are equal when the valve member is in a central position, and so the pressure on either side of the jet is the same and the jet is not deflected. When the valve member is in any other position, the passages, and therefore the pressures on both sides of the jet, differ from one another and the jet is deflected proportionally to the pressure difference which it experiences.

In a dense atmosphere the distributor is connected to a pressurised fluid source. The flow is in countercurrent to the arrows, and deflection of the power jet is proportional to the difference between the movement quantities and/or the static pressures operative via the control passages.

If required, the jet could be deflected by means of separate valves each associated with a control slot and not necessarily supplying the respective control slot simultaneously.

Of course, the embodiments hereinbefore described can be modified, inter alia by the substitution of equivalent technical means, without for that reason departing from the scope of this invention. More particularly, the wall portions 9a, 9b can be curved instead of plane.

What we claim is:

1. A jet deflector of use as the downstream part of a propulsive and piloting system for a flying body, comprising in combination:

a nozzle which is adapted to deliver a propulsive gas jet and which is divergent in at least a portion near the nozzle exit end;

a deflecting chamber which is connected to the last-mentioned end coaxial of the nozzle and which is bounded:

at its upstream end, by an end which extends transversely of the nOZZle axis and which projects on either side of the nozzle exit orifice;

laterally, by walls substantially parallel to the nozzle axis and tangential to the nozzle exit orifice, and by partially convergent walls which are connected to the projecting ends of the chamber end and to the parallel walls, the edges of the convergent portions being apart from one another by a distance greater than the corresponding dimension of the nozzle exit orifice so as to bound an exit orifice through which the propelling jet issuing from the nozzle can depart from the chamher, and so as to leave lateral spaces between at least that portion of the said partially convergent walls adjacent the chamber end and the propelling jet;

the chamber also being formed near each of the ends projecting beyond the nozzle end with at least one orifice and provision for selectively connecting the lateral spaces via such orifices to fluid media at appropriate pressures.

2. A jet deflector as set forth in claim 1 characterised in that the nozzle portion near the nozzle exit end has substantially the shape of a rectangle whose major sides are parallel to the partially convergent walls.

3. A jet deflector as set forth in claim 1 characterised in that the nozzle portion near the nozzle exit end has a circular crosssection.

4. A jet deflector as set forth in claim 1 characterised in that the width of the chamber end in the direction in which the same projects beyond the nozzle exit orifice is approximately twice the width thereof in the same direction, and chamber length is substantially ten times the lastmentioned width.

References Cited UNITED STATES PATENTS 1,493,157 5/1924 Melot 239265.l7 2,597,253 5/1952 Melchior 239-26517 2,914,916 12/1959 Gelin et al 239265.17

EVERETT W. KIRBY, Primary Examiner.

U.S. DEPARTMENT OF COMMERCE PATENT OFFICE Washington, DC. 20231 UNITED STATES PATENT OFFICE CERTIFICATE OF CORRECTION Patent No. 3,401,885 September 17, 1968 Cyrille Francois Pavlin et al.

It is certified that error appears in the above identified patent and that said Letters Patent are hereby corrected as shown below Column 2, line 5, "FIG. 2" should read FIG. 1

Signed and sealed this 10th day of March 1970.

(SEAL) Attesti WILLIAM E. SCHUYLER, JR.

Edward M. Fletcher, Jr.

Commissioner of Patents Attesting Officer 

